3 Answers
3

Ableton Live can output MIDI notes/CCs pretty easily, so if you have visualization software that can use this to trigger visualizations, you should be set - you can just wire them togeter with some virtual-MIDI-port software (Bome's or OSX IAC or something like that).

Ableton also has some kind of MIDI Sync feature, although I hear it's fairly buggy. I've not tried it myself.

Finally, if you have the Max 4 Live addon, you can probably make a patch to sync up video using OSC or any pre-built tools for Max. Again, I've not tried this, as I don't have Max 4 Live.

Doesn't Live support video loading and syncing in recent versions? I remember seeing a screenshot somewhere of someone's project where he had loaded up a video and was working on the music synced to the video. But this is during production, and not live performance.

If you're looking for a solution that works during live performance, you can run a VJ package simultaneously with Live, like Resolume or Avenue, of perhaps Modul8 if you are on Mac. If you want to program stuff yourself you can get into Max/MSP or Max4Live like already mentioned by Warrior Bob, or Processing, which you mentioned yourself.

If you'd rather create visuals yourself as performer, synced with your music, and you don't want to use video, you can use an audiovisual tool like AudioCubes by Percussa, which can sync to Ableton Live's tempo, and which can accept MIDI CC messages for colour mixing (which you can send from within Ableton Live MIDI clips).